refactor(examples): fix typos (Kotlin#39)

Author: wmorgue

_examples/nullSafety.md

@@ -3,7 +3,7 @@ title: Null Safety
 ---
 
 
-In an effort to rid the world of `NullPointerException`, variable types in Kotlin don't allow the assigment of `null`.
+In an effort to rid the world of `NullPointerException`, variable types in Kotlin don't allow the assignment of `null`.
 
 <div class="sample" markdown="1">
 
@@ -27,7 +27,7 @@ fun main(args: Array<String>) {
 1. Declare a non-null String variable
 2. Declare a nullable String variable
 3. Set the nullable variable to null
-4. When infering types, the compiler assumes non-null for variables that are initialized with a value
+4. When inferring types, the compiler assumes non-null for variables that are initialized with a value
 
 ### Working with nulls
 

_examples/ranges.md

@@ -56,6 +56,6 @@ fun main(args: Array<String>) {
 4. Increment step for char ranges are also valid
 5. To create a range in _reverse_ order use `downTo()` function
 6. Ranges are also useful in `if` statements
-7. `!in` is oposite of `in`. Statement is equal to `_false_`
+7. `!in` is opposite of `in`. Statement is equal to `_false_`
 
 

examples/01_introduction/04_Null Safety.md

@@ -1,6 +1,6 @@
 # Null Safety
 
-In an effort to rid the world of `NullPointerException`, variable types in Kotlin don't allow the assigment of `null`.
+In an effort to rid the world of `NullPointerException`, variable types in Kotlin don't allow the assignment of `null`.
 
 <div class="language-kotlin" theme="idea" data-min-compiler-version="1.3">
 
@@ -28,7 +28,7 @@ fun main() {
 2. Trying to assign `null` to non-nullable variable produces a compilation error. 
 3. Declare a nullable String variable.
 4. Set the nullable variable to `null`.
-5. When infering types, the compiler assumes non-`null` for variables that are initialized with a value.
+5. When inferring types, the compiler assumes non-`null` for variables that are initialized with a value.
 
 ## Working with nulls
 

examples/02_control_flow/03_Ranges.md

@@ -52,5 +52,5 @@ fun main() {
 4. Increment step for char ranges are also valid
 5. To create a range in _reverse_ order use `downTo()` function
 6. Ranges are also useful in `if` statements
-7. `!in` is oposite of `in`. Statement is equal to `_false_`
+7. `!in` is opposite of `in`. Statement is equal to `_false_`
 

examples/03_special_classes/01_Data classes.md

@@ -39,7 +39,7 @@ fun main() {
 2. Auto-generated `equals` makes data classes with equal information equals as well.
 3. Equal data classes have equal `hashCode()`.
 4. Predefined `copy` function makes it easy to obtain a new instance.
-5. Property values can be changed on copy. The order corresponds to contructor argument order.
+5. Property values can be changed on copy. The order corresponds to constructor argument order.
 6. It is possible to change only some values.
 7. Use named arguments to change the second value without altering the first one.
 8. Additionally special `componentN` functions are generated.

examples/05_stdlib/03_filter.md

@@ -1,6 +1,6 @@
 # filter
 
-*filter* is a function defined in the standard library that can be used to filter collection. It takes a predicate as an lambda-paramters. 
+*filter* is a function defined in the standard library that can be used to filter collection. It takes a predicate as an lambda-parameters. 
 
 <div class="language-kotlin" theme="idea" data-min-compiler-version="1.3">
 
@@ -16,8 +16,8 @@ fun main() {
 //sampleEnd
 
     println("Numbers: $numbers")
-    println("Positive Numbers: positives")
-    println("Negative Numbers: negatives")
+    println("Positive Numbers: $positives")
+    println("Negative Numbers: $negatives")
 }
 ```
 

examples/05_stdlib/04_map.md

@@ -1,6 +1,6 @@
 # map
 
-*map* is an extension function defined in the standard library that can be used to transform collection into another collection. It takes a transformer as an lambda-paramters.
+*map* is an extension function defined in the standard library that can be used to transform collection into another collection. It takes a transformer as an lambda-parameters.
 
 <div class="language-kotlin" theme="idea" data-min-compiler-version="1.3">
 

examples/05_stdlib/05_existential.md

@@ -79,7 +79,7 @@ fun main() {
     val allLess6 = numbers.none { it > 6 }               // 3
 //sampleEnd
 
-    println("Numbers: numbers")
+    println("Numbers: $numbers")
     println("All numbers are even: $allEven")
     println("No element greater than 6: $allLess6")
 }

examples/05_stdlib/06_find.md

@@ -27,4 +27,4 @@ fun main() {
 1. Define collection of different words.
 2. Looking for the first word starting with "some".
 3. Looking for the last word starting with "some".
-4. Lookign for the first word containing "nothing".
+4. Looking for the first word containing "nothing".

examples/05_stdlib/11_zip.md

@@ -24,4 +24,4 @@ fun main() {
 
 1. Define two collections.
 2. Zip them into pairs using infix notation.
-3. Zip them concatinating together.
+3. Zip them concatenating together.